}
	args, err := quoted.Split(string(cxx))
	if err != nil {
		t.Skipf("could not parse 'go env CXX' output %q: %s", string(cxx), err)
	}
	if len(args) == 0 {
		t.Skip("no C++ compiler")
	}
	testenv.MustHaveExecPath(t, string(args[0]))
}

var (
	swigOnce sync.Once
	haveSwig bool
)

func mustHaveSwig(t *testing.T) {
	swigOnce.Do(func() {
		mustHaveSwigOnce(t)
		haveSwig = true
	})